#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (c) 2022 Virtual Cable S.L.U.
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"""
Author: Adolfo Gómez, dkmaster at dkmon dot com
"""
import typing

hasher: typing.Any

import hashlib


def hash_key(key: typing.Union[str, bytes]) -> str:
    """
    Returns a hash of the given key
    Return value should be, at most, 64 bytes long (as db field is 64 bytes long)
    Currently used at least on:
        * src/uds/core/util/cache.py
        
    Note that replacing the algorithm used here will force to invalidate all previous generated
    entries. In the case of cache, this is not a problem, but in other cases, it could be.
    
    Currently, we are using sha256, that generates a 64 bytes long hash
    Blake2b is also a good candidate
    """
    if isinstance(key, str):
        key = key.encode('utf-8')

    return hashlib.sha256(key).hexdigest()
